Smart Building

The Importance of Grounding and Bonding a Shielded System in the Telecommunications Room

Ron Tellas

A grounding and bonding system is helpful in protecting your data center and networking equipment, and ensuring that your shielded twisted-pair structured cabling system is reliable and high performing – and isn’t being impacted by transmission errors or unwanted noise.

But, in our industry, the terms “grounding” and “bonding” are often confused or misused. For example, connecting a lug or piece of metal to a data center rack is often thought of as “grounding” the system – but that process actually “bonds” the system instead.


The Differences Between Grounding and Bonding

Grounding (typically handled by electricians) involves the creation of an electrical connection to earth ground; essentially, it’s a copper pole driven into the ground so that all electrical utilities can be connected to it.


“Bonding” involves bonding to that grounding system. Bonding equalizes the ground potential of equipment, and eliminates static discharge between devices.


In a successful grounding and bonding system, electromagnetic interference noise is carried to ground along a shield that protects data from being impacted by that noise during transmission. Any metal component of your networking or data center infrastructure should be bonded to your grounding system.


Determining who’s responsible for installing a grounding and bonding system can be tricky. Some believe that integrators and other cabling installers have a responsibility to recognize and understand grounding and bonding systems; others say that the responsibility lies elsewhere (because bonding is done to a grounding system that the low-voltage installer isn’t responsible for).


We think it’s important for everyone involved in cabling and connectivity to understand both grounding and bonding, but professionals in the telecommunications industry should primarily be focused on ensuring proper bonding.


How Bonding Works

A bonding system in a multi-level building works like this:

  1. The primary bonding busbar (PBB) is located on the lowest level of a building, and is attached to the grounding system (installed by the electrician).

  2. From the PBB runs a telecommunications bonding backbone (TBB), which is a thick-diameter copper wire. It runs up through each floor of the building to reduce differences between telecommunications systems on different floors.

  3. Each floor of the building has a secondary bonding busbar (SBB).

  4. The TBB runs continuously to connect all of the SBBs to the PBB on the lowest level of the building.

  5. The cable’s shielding system attaches to the SBBs and TBBs in the grounding system.

  6. If the building has equipment runs on each side, the same scenario holds true for the other side of the building, too (then, at the top, the two TBBs connect).

ANSI/TIA-607-C, Generic Telecommunications Bonding and Grounding for Customer Premises, encourages the planning, design and installation of telecommunications grounding and bonding systems in new buildings, renovations or retrofits. Per these standards, Belden bonds its cable shields for proper system performance. In addition, the third prong on all Belden equipment is considered a ground – but only if it has a good path to earth ground.


Want to learn more about grounding and bonding? Make sure you subscribe to our blog. Soon, we’ll cover another component of the grounding and bonding process: effective shielding systems.